英语四级快速阅读题Today,almost two-thirds of those who develop cancer

英语四级快速阅读题Today,almost two-thirds of those who develop cancer will still be alive five years later,compared with just half in 1970s.In the 1970s,only one-third of those who developed cancer could be alive five years later.两句话的意思一样不?那第一句如果继续用compared和half应该怎么改成1970s只有1/3的人能活5年的意思呢